What is the amygdala?

The amygdala is a subcortical area found in the temporal lobe, comprising part of the limbic system. It is heavily involved in emotion regulation, memory and control, especially in anger, aggression, and fear. Stimulation of the amygdala can cause fear and anxiety. When a stimulus has been conditioned to be fearful, the stimulus will activate the amygdala, which will cause the fear response. In conditions like PTSD, which involves high levels of anxiety, the amygdala is overactive.Neuropsychology looks at brain damaged patients to figure out what those brain areas do. A famous example of a patient with complete amygdala damage is Patient SM, who would cognitively know that something was scary or dangerous, but feel no fear. She would, however, feel other emotions, suggesting fear is located in the amygdala but other emotions, despite using the amygdala, have other locations too. For a wider example of amygdala neuropsychology, diagnosed psychopaths on average show a dysfunctional amygdala, related to impaired emotion regulation and aggression.